INDEX. 



689 



Petalocrinus, 411 



mirabilis, 403 

 Phacops logani, 455 



rana, 471 

 Phalen, W. C, cited, 28 

 Phillips, J., cited, 410 

 Phillipsia, 618 



major, 616 

 Phinney, A. J., cited, 336 

 Phlegethontia, 608 

 Phobos, 10 



revolution of, 63 

 Pholidogaster, 538 

 Phosphates, Devonian, 440 



Ordovician, of Tennessee, 337 

 Photobathic life, 292 

 Phragmoceras nestor, 403 

 Phyllocarids, Devonian, 490 

 Phyllograptus, 364 



cambrensis, 287 



ilicifolius, 362 



typus, 362 

 Phyllopods, Devonian, 490 

 Phylloporina granistriata, 358 

 Phyllotheca, 646 



indica, 645 

 Physa prisca, 528 

 Pittsford shale, 389 

 Placodontia, 651 

 Planetary nuclei, 61 



growth of, 64, 67, 78 

 Planetary orbits, shifting of, 78 



rings and rotation, 70 



rotation, 70-75 



on accretion hypothesis, 70 

 Planetary rings, formation of, 



4 

 Planetary rotation on Laplacian 



hypothesis, 70 

 Planetesimal collisions, 66, 72 



condition, from gaseous spher- 

 oid, 39 

 from meteorites, 40 

 from original nebular dis- 

 persion, 40 



hypothesis, deformations un- 

 der, 122 

 early stages of earth under, 



9i 

 sub-varieties of, 38 



infall, effect on temperature, 

 68 



motions, 64 



nebulae, 48 



orbits elliptical, 72 

 Planets, eccentricities of, 79 



origin of, 60 



spacing out of, 78 

 Plant-growth, influence of car- 

 bon dioxide on, 605 

 Plant life of Cambrian, 278 



Carboniferous, 591 



Devonian, 491 



Mississippian, 537 



Ordovician, 346 



Pennsylvanian, 591 



Permian, 642 



Silurian, 409 

 Plateaus, possible origin of, 124 

 Platephemera antiqua, 494 



Plalyceras dumosum, 462 



gibbosum, 455 



nodosus, 459 



pnmaevum, 297 



spirale, 455 

 Platycrinus, 522 



gorbyi, 525 



verrucosus, 525 

 Platyostoma broadheadi, 520 

 Platysomus, 652 



gibbosus, 653 

 Platystrophia bitorata, 367 



lynx, 356 

 Pleasonton shales, 561 

 Plectambonites sericeus, 356. 



367 

 Plectorthis newtonensis, 299 

 Pleurocystis fiTitextus, 359 

 Pleurotomaria nodulostnata, 532 

 Pocahontas formation, 559 

 Pocono sandstone, 500, 502, 557. 



558 

 Pokegama quartzite, 189 

 Polypora lilaea, 455 

 Popanoceras, 655 



walcotti, 654 

 Porcellia nodosa, 520 

 Portage formation, 432 

 Post-Cambrian and pre-Cam- 



brian evolution, 293 

 Post-Permian deformation, se- 

 quences of, 658, 660 

 Potean beds, 562 

 Poterioceras apertum, 352 

 Potonie, H., cited, 595 

 Potsdam series, 219, 225 

 Potassium salts in Pennsyl- 

 vania, 630 

 Pottsville series, 539. 542, 557. 



558, 560 

 Powell, J. W., cited, 153, 210 

 Pre-Cambrian and Post-Cam- 

 brian evolution, 293 

 Prestwichia danag, 611, 613 

 Price sandstone, 559 

 Primitive gneiss, 142 

 Princeton conglomerate, 559 

 Prodromites gorbyi, 520 

 Productella, 465, 478 



Mississippian, 528 



pyxidata, 520 



spmulicosta, 462 

 Productids, 465 



Genevieve, 531 



Hamilton, 472 



Mississippian, 528 

 Productus, 465, 615 



arcuatus, 520 



burlingtonensis, 525 



cora, 617 



costatus, 616, 617 



fasciculatus, 532 



marginicinctus, 532 



nebrascensis, 616, 617 



semireticulatus, 617, 653 



symmetricus, 616, 617 

 Proetus ellipticus, 520 



parviusculus, 349 

 Proganosauria, 649 

 Progonoblattina columbiana, 611 



Prosser, C. S., cited, 250, 318, 

 420, 434, 500, 502, 511, 

 540, 542, 546# 558, 560, 

 619, 621, 622, 653 

 Proterosauria, Permian, 649 

 Proterozoic, Adirondack region, 

 205 



Black Hills, 174 



contrasted with Archeozoic* 

 139 



Cordilleran region, 210 



duration ot, 198 



eastern provinces of Canada, 

 204 



Eastern United States, 211 



era, 162 



climate of, 217 



exposures of, 202 



extra- American, 215 



great northern area, 203 



Green mountains, 213 



Lake Superior region, 175 



life, 216 



map of, 147 



Marquette region, 174, 176 



Minnesota, 173, 174 



New Jersey, 213 



original Laurentian area, 204 



outside Lake Superior region^ 

 202 



relations to Archean, 139, 

 171 



Rocky mountains, 174 



sedimentation, 166 



sediments, extent of, 168 



South Dakota, 173 



southeastern Missouri, 209 



stratigraphic relations ot, 163 



subdivisions of, 165 



succession, Lake Superior re- 

 gion, 200 



system, rocks of, 169 



Wyoming, 210 

 Protobalanus hamiltonensis, 471 

 Protocaris marshi, 283 

 Protopterus, 487 

 Protorhyncha antiquata, 285 

 Protorosauna, 647 

 Protorthis billingsi, 298, 299 

 Protowarthia cancellata, 353 

 Protozoa, Cambrian, 287 



Carboniferous, 616, 618 



Devonian, 467 's 



Genevieve, 531, 532 ? 



Ordovician, 361 

 Protremata, 356 

 Provincial development of Ordo^ 



vician life, 343 

 Psaromus, Devonian, 493 

 Pseudopecopteris, Mississippian, 



537 

 Psilophyton, 494 

 Pteraspis, 484, 485 

 Pteridophytes, 592 



Devonian, 492, 493 

 Pteridospermae, Devonian, 493 



Pennsylvanian, 595 

 Pterinea demissa, 354 



emacerata, 403 



flabella, 471 



